Ima Fungus最新文献

The order Cribrariales is among the least studied higher groups in the Myxomycetes, with numerous taxonomic problems and scarce molecular data available in public databases. Of the three genera currently accepted, viz. Cribraria, Lindbladia, and Enteridium, the last one shows a set of morphological characters clearly disagreeing with the two former ones. Using a representative sampling and two unlinked loci (nuclear and mitochondrial SSU), we assessed the phylogenetic relationships in the bright-spored Myxomycetes (Lucisporomycetidae) and concluded that the genus Enteridium must be excluded from the order Cribrariales and placed instead within the order Trichiales, family Dianemataceae. We provide detailed explanations of why this genus has been misclassified in previous studies, and define its morphological and molecular boundaries, performing two necessary new combinations. On the other hand, the phylogeny of the order Cribrariales s.str. shows three main lineages that are distinguished as three subgenera, viz. C. subg. Cribraria, C. subg. Dictydium, and C. subg. Ionokylixsubg. nov., the first one including the genus Lindbladia deeply nested and therefore treated as a heterotypic synonym of Cribraria.

Although the kojic acid gene cluster in Aspergillus oryzae was identified in 2010, the functions of neighbouring genes remain poorly understood. Here, we characterise Aokap7, a gene adjacent to this cluster that encodes a novel nucleus-localised zinc finger protein without transcriptional activation activity. Disruption of Aokap7 markedly accelerated spore germination, hyphal growth, and conidial formation, but impaired kojic acid production. Overexpression of kojR or laeA restored kojic acid production in the Aokap7 disruption strain, whereas their disruption abolished it, indicating that Aokap7 regulates kojic acid production by kojR and laeA. Furthermore, disrupting Aokap7 in the AozfA overexpression or disruption strains reversed their kojic aicd production, suggesting that Aokap7 acts downstream of AozfA. The Aokap7 mutant also exhibited reduced expression of reactive oxygen species (ROS)-scavenging genes and heightened oxidative stress sensitivity. Biochemical assays revealed that Aokap7 preferentially binds to the motif 5'-CGGCTCGG-3', and directly interacts with the AoGPX1 promoter. Disruption of AoGPX1 increased the sensitivity of A. oryzae to oxidative stress. Our findings elucidate the pivotal role of Aokap7 in coordinating growth, oxidative stress response and kojic acid production, advancing understanding of the regulatory network of kojic acid synthesis in A. oryzae.

Populus euphratica is a key deciduous and tall arbour capable of forming forests in arid and desert environments, exhibiting notable tolerance to drought, salinity and bacterial resistance. This study completed whole-genome sequencing of Inonotus hispidus and Inocutis levis, collected from Xinjiang, China, to predict genome structure and identify potential drought-related genes. Combined with transcriptome sequencing under different drought conditions simulated using PEG-6000, the gene expression regulation during drought tolerance was analysed. Whole-genome sequencing was carried out on the Illumina Novaseq and Pacbio Sequel platforms, resulting in genome size of 34.57 Mb for Inonotus hispidus and 37.17 Mb for Inocutis levis, respectively. A total of 10,169 and 10,140 protein-coding genes were annotated in these two species. The genomes of two species exhibited high synteny with 7,226 shared homologous genes and their functional annotations showed high similarity. Under drought stress at three PEG-6000 concentrations (10%, 30% and 50%), the transcriptomic analyses revealed 4,550 and 2,113 differentially expressed genes (DEGs) in the two fungi, respectively, with an increasing number of up- and down-regulated genes as the drought stress intensified. Gene expression profiles in response to drought stress showed prominent changes, amongst which the genes related to antioxidation, osmotic regulation, signal transduction and ribosomal function may play important roles. In the ribosome pathway, Inonotus hispidus showed a significant down-regulation of ribosomal-related genes under mild drought stress, which is up-regulated once again as the stress intensifies, while Inocutis levis exhibited significant up-regulation of these genes under severe drought stress, highlighting distinct drought adaptation strategies. This study provides essential theoretical insights into the molecular adaptation mechanisms of fungi in dry environments and offers new perspectives for the development of microbial resources in arid regions.

The ecological role of Ischnoderma benzoinum in conifer stands remains poorly understood, particularly with regard to its potential to compete with the root rot pathogen Heterobasidion annosum. This study investigated the growth dynamics, wood decay capacity, and competitive interactions of two I. benzoinum isolates (originating from Pinus sylvestris and Picea abies) with two H. annosum isolates from the same host species, and with the biocontrol fungus Phlebiopsis gigantea. Laboratory assays involved growth on malt extract agar for 14 days, and single and dual inoculations on pine and spruce wood for 60 and 120 days. Both I. benzoinum isolates exhibited growth rates on medium comparable to those of H. annosum. On spruce wood, I. benzoinum caused the greatest mass loss, whereas H. annosum dominated on pine. In most dual cultures, wood mass loss was similar to that in single cultures; however, in the pairing of the spruce-derived I. benzoinum with P. gigantea, decay was significantly reduced, indicating antagonistic interaction. Competitive outcomes in dual cultures varied markedly. The pine-derived I. benzoinum strongly suppressed the pine-derived H. annosum, whereas the spruce-derived H. annosum consistently outcompeted both I. benzoinum isolates. P. gigantea strongly inhibited I. benzoinum mycelial growth and frequently reduced its decay activity. These findings demonstrate that I. benzoinum can function either as a strong competitor or as a co-colonizer with H. annosum, with interaction outcomes determined by isolate origin and host tree species. The capacity of I. benzoinum to match H. annosum in wood decay efficiency, particularly on spruce, suggests that it may influence disease progression and nutrient cycling in coniferous forests. This work advances understanding of fungal community dynamics in wood decomposition and highlights the need for further ecological and molecular studies to clarify the role of I. benzoinum in forest health and management.

The Onygenales represent a versatile group of fungi that primarily inhabit soils, degrading cellulose and/or keratin. While some are known human pathogens, others are osmotolerant or colonize chitin substrates such as insects. The marine environment, characterized by 3.5% salinity and chitin as the dominant polysaccharide, represents an intriguing niche for these fungi. However, fungal diversity in this environment remains poorly studied. This study investigated the culturable diversity of Onygenales in marine sediments, explored their global biogeography, and assessed their adaptability to marine conditions. Marine sediments were collected near river mouths and other coastal areas along the Catalan coast (Spain). Identification was based on a polyphasic approach; global distribution patterns were assessed through the GlobalFungi database, and adaptability was evaluated through osmotolerance and substrate degradation assays (cellulose, chitin, keratin). We recovered 32 strains, of which 24 represented 16 known species distributed in Gymnascella, Gymnoascus, Narasimhella, and Sporendonema (Gymnoascaceae); Malbranchea (Malbrancheaceae); Myriodontium (Neoarthropsidaceae); and Aphanoascus and Byssoonygena (Onygenaceae). The remaining eight strains were delineated as six novel species, including a new genus: Gymnoascoideus alboluteus sp. nov., Malbranchea parafilamentosa sp. nov., M. sedimenticola sp. nov., M. seminuda sp. nov., M. sexualis sp. nov., and Deilomyces minimus gen. et sp. nov. In addition, all strains degraded cellulose, and most tolerated up to 10% NaCl. Only four species that also degraded chitin (Malbranchea parafilamentosa, M. sexualis, Myriodontium keratinophilum, and Sporendonema casei) could be considered facultative marine fungi. This work evidences the great diversity of onygenalean fungi in marine sediments and underscores their metabolic adaptability to marine conditions.

Phlebopus portentosus is a widely consumed edible mushroom and the only Boletales species currently cultivated on an industrial scale. Despite its economic importance, its trophic strategy and genomic adaptations remain elusive. Here, we presented high-quality, chromosome-level genome assemblies for two sexually compatible monokaryons (PP78 and PP85) of P. portentosus. Comparative genomic analysis revealed a genome size difference of 1.17 Mb (30.87 vs. 32.04 Mb), primarily attributed to transposable element (TE) expansion in strain PP85. Genome structural variations were largely driven by TEs, particularly LTR retrotransposons. DNA transposons were also involved in structural rearrangement of secondary metabolite biosynthetic gene clusters, impacting their organization and transcriptional profiles. Functional annotation identified 187 PP78-specific and 236 PP85-specific genes, with the latter enriched in TE-related and putative virulence factors. P. portentosus displays genomic signatures of both ECM symbiosis (reduced lignocellulose-degrading enzymes) and saprotroph (expanded glycoside hydrolase 31 and sugar transporters), supporting a facultative ECM lifestyle. The expansion of non-ribosomal peptide synthetase and polyketide synthase pathways, alongside contraction of terpenoid clusters typical of ECM fungi, further indicated its adaptation to saprotroph. These findings highlight the role of TEs in driving genome plasticity, metabolic diversity, and nuclear divergence in P. portentosus, providing valuable genomic resources for this species.

Boletaceae, the largest family in the Boletales order, is an ecologically and economically important group and the phylogenetic studies of this group need to be further developed. The mitogenome is an effective molecular marker for analysing phylogenetic relationships; however, Boletaceae mitochondrial genome (mitogenome) has been studied to a lesser extent. Thus, a comparative analysis of the mitogenomic features of seven Boletaceae species, representing seven distinct genera, was conducted. Phylogenetic relationships amongst these species within Boletales were reconstructed, based on the mitogenomic data. Highly consistent phylogenetic results within 34 Boletales species and two outgroups from Polyporales, based on mitogenomic datasets, were obtained using Maximum Likelihood and Bayesian Inference methods. Results of phylogenetic analyses revealed that Boletus, Retiboletus and Neoboletus were polyphyletic. Interestingly, species of Neoboletus with different bruising discolouration patterns were found in separate clades, suggesting this trait may reflect underlying genetic divergence. Furthermore, comparative and phylogenetic analyses revealed gene re-arrangements in mitogenomes of Boletaceae. This study is the first to report on complete mitogenomes of four genera (Amoenoboletus, Hourangia, Leccinum and Strobilomyces) and will help better understand the phylogenetic relationships of Boletales. Furthermore, addition of more new taxa is necessary to reconstruct a high-resolution tree.

The genus Xylaria is a promising source of bioactive compounds. This study examined the diversity of secondary metabolites (SMs) in Xylarialongipes under three fermentation conditions, resulting in the isolation of 14 new SMs and 27 known ones. The structures, including absolute configurations, were determined using NMR spectroscopy, HRESIMS analysis, and computational methods (ECD, ¹³C NMR data, and optical rotation). A comprehensive library of SMs was established, enabling metabolomics-wide association studies that identified culture conditions as a key factor influencing SM production. This compound library also facilitates the determination of absolute configurations for diplosporins by analyzing J values and CD trends. Anti-proliferative tests against induced T/B lymphocytes and HaCaT cells revealed that over half of the compounds exhibited significant inhibitory activity, with compounds 2, 15, and 32 reducing IFN-γ secretion. Compound 32 demonstrated promising anti-psoriatic effects by inhibiting NF-κB p65 phosphorylation in HaCaT cells. This initial systematic chemical study of X.longipes under different conditions provides insights into structure-activity relationships.

Morchella species, commonly known as true morels and being cold-preferring fungi, are esteemed for their distinctive flavor as well as significant economic and prominent research value. Chongqing, located in southwestern China and renowned as the "Furnace City" due to its distinctive climate and extremely high summer temperatures, spans an area of 82,400 square kilometers with complex geographical topography, yet has lacked a comprehensive survey of true morels (Morchella) so far. From 2017 to 2024, we conducted extensive field surveys across 13 districts and counties within Chongqing, resulting in the collection of over 1,000 wild morel samples. Through a combination of multi-gene phylogenetic analysis and microscopic morphological observations, we uncovered a surprisingly high level of species richness of Morchella in Chongqing, identifying 13 species in the Esculenta clade (yellow morels) and three species in the Elata clade (black morels), including six newly described species: Morchellachinensis sp. nov., M.diversa sp. nov., M.eoa sp. nov., M.huoguo sp. nov., M.montana sp. nov., and M.universitatis sp. nov. Notably, M.nipponensis, previously documented only in Japan, is reported for the first time in China. Furthermore, significant divergence in species diversity between the Esculenta and Elata clades of Morchella has been observed in Chongqing, which is strongly influenced and shaped by the prevailing vegetation. The distribution pattern of Morchella species suggests that the impact of high summer temperatures on species diversity in Chongqing is partially mitigated by locally diverse mountainous habitats. In addition, the habitats of M.diversa and M.universitatis, the two most widely distributed species in Chongqing, exhibit higher vegetation diversity, suggesting that Morchella species with greater habitat adaptability tend to have broader geographic ranges. This study provides valuable insights into the species diversity and distribution pattern of Morchella, particularly in a region with unique climatic and ecological conditions, and highlights the need for further study into the correlation between vegetation and Morchella species.

As part of an ongoing study of marine fungi associated with seagrasses, we discovered a novel root-fungus symbiosis in the Indo-Pacific species Thalassodendronciliatum from Mauritius. Culturing its mycobionts yielded dozens of morphologically and genetically uniform isolates, all representing a previously unknown fungus. A second undescribed fungus was isolated from saline soils in Czechia. Phylogenetic analyses based on three rDNA markers confirmed both taxa as distinct, hitherto unknown lineages within the Lulworthiales, which are introduced here as Thalassodendromycespurpureus gen. et sp. nov. and Halomyrmapluriseptata gen. et sp. nov., respectively. Both species developed characteristic structures under culture conditions that enabled their morphological characterisation: T.purpureus forms distinctive clusters of dark brown monilioid hyphae, while H.pluriseptata is characterised by holoblastic conidiogenesis and solitary, dark brown, multicellular conidia. Thalassodendromyces clustered in a strongly supported clade with Spathulospora, a parasitic genus of the red macroalga Ballia, while the closest relatives of Halomyrma were identified as the asexual genera Halazoon and Halophilomyces (nom. inval. Art. 40.7). An analysis of published metabarcoding ITS rDNA data from environmental samples in the GlobalFungi database indicated that H.pluriseptata is widely distributed across temperate, subtropical, and tropical regions in the Northern and Southern Hemispheres. The species exhibits a strong preference for aquatic biomes, particularly marine and estuarine, with a few records in terrestrial ecosystems. In contrast, no record of T.purpureus was retrieved from GlobalFungi, suggesting narrower ecological specialisation, a close association with its seagrass host, and/or a restricted geographical range. Our findings expand the ecological and phylogenetic scope of the Lulworthiales, bridging marine and terrestrial fungal communities, and highlight seagrass roots as an important source of novel symbiotic marine fungi. Recent discoveries of the Lulworthiales in saline inland soils challenge their marine exclusivity and raise important questions about their ecological plasticity, dispersal mechanisms, and adaptive strategies. In light of current observations, we discuss the taxonomic challenges of the Spathulosporales and the lulworthialean fungi, integrating molecular and morphological perspectives. We address the importance of combining morphological and molecular approaches to accurately delineate new fungal taxa, as well as the value of environmental DNA metabarcoding for uncovering cryptic fungal diversity and enhancing our understanding of fungal distribution and ecological functions.